1. Field of the Invention
The present invention relates to a facsimile machine and more particularly, to a technique for copying a multipage document in a facsimile machine.
2. Description of the Related Art
Generally speaking, a facsimile machine divides a still image, such as characters, photographs and pictures, into picture elements through scanning, and converts them into electrical signals for the purpose of transmission. In addition to this operation, the facsimile machine performs reception in which the original image transmitted is realized, after receiving the electrical signals transmitted from a long distance. Such a facsimile machine which performs transmission and reception typically has at least a document feed roller for transporting a document, a scanner for scanning image information written on the document transported by the document feed roller, a paper feed roller for transporting sheets of paper for printing the image information read by the scanner, and a CPU for controlling their operations.
Advanced facsjmile machines perform a copying operation as well as transmission and reception so that users may have additional convenient functions. For instance, Korean Utlity Model Application No 95-28546 filed by the Applicant and entitled Motor Driving Apparatus For Facsimile, discloses a facsimile which performs a copying operation as well as transmission and reception. The facsimile machine's document copying procedure is divided into two parts: transporting the document to be copied to the scanning position, and transporting sheets of paper to copy the transported document. These operations can be applied even to the case of copying a multipage document. More specifically, during multipage document copying, the facsimile machine copies the first page of the document, and then controls the gear mode to the transmission mode in order to copy the second page of the document so that the document is transported to the scanning position. After this procedure, the facsimile machine returns the gear mode to the copying mode so that the second page of the document is transported to the copying position to be copied the transported copy paper. Then, the facsimile machine repeats the above-explained operations in order to copy the third page of the document.
Most of the facsimile machines comprising the document feed roller and paper feed roller, including the facsimile machine disclosed in the aforesaid Utility Model Application, take long time to copy a document. This is because of the fact that, during multipage copying, the facsimile machine must transport the document to be copied after the gear mode is switched to the transmission mode from the copying mode, and then the gear mode must be switched to the copying mode for copying. Specifically, during multipage copying, the facsimile machine takes time to switch from the copying mode to transmission mode, time to transport the document in the document transmission mode, and time to switch from the transmission mode to the copying mode. It takes longer time to copy as the number of documents increases.
The following patents each disclose features in common with the present invention but do not teach or suggest the specifically recited technique for copying a multi-page documents in a facsimile machine in accordance with the present invention.
U.S. Pat. No. 5,589,953 to Tazawa et al., entitled Image Input System Having An Auto-Feeder Including Loading Magazine And Discharge Magazine Arranged Side By Side And Method, U.S. Pat. No. 5,555,349 to Miyasaka et al, entitled Printing Device And Recording Paper Control, U.S. Pat. No. 5,534,973 to Harada, entitled Automatic Document Feeder For Photocopier And Facsimile Device, U.S. Pat. No. 5,513,017 to Knodt et al., entitled Automatic document Imaging Mode Selection System, U.S Pat. No. 5,379,128 to Ishida et al., entitled Document Transport Apparatus And Method, U.S. Pat. No. 5,239,395 to Kang et al., entitled Transmission/Copy Method And Device For A Two-Way Scanning Facsimile, U.S. Pat. No. 5,216,526 to Ju, entitled Method For Controlling Paper-Feeding By Detecting A Starting Point Of Scanning In A Facsimile System, U.S Pat. No. 5,194,970 to Iwanade, entitled Automatic Original Feeding Device, U.S. Pat. No. 5,060,080 to Hwang, entitled Self Multi-Copy Method In A Facsimile System, and U.S. Pat. No. 4,663,122 to Sato, entitled Automatic Paper Feed Control Apparatus For A Painting Device.